Holotype (PDD 27017); Isotype Herb. HK. ZT 69/209): 'Denton River, Te Anau Downs, prov. Southland, N.Z.; leg. Horak, 1.IV.1969'. - Herb. HK. ZT 67/203: 'Kowai River, Mt. Grey, prov. Canterbury, N.Z; leg. Horak, 2.XII.1967'. - Herb. HK. ZT 68/183: 'S of Ahaura, Ngahere, prov. Westcoast, N.Z.; leg. Horak, 18.III.1968'.

Pileus 5-12 mm diam., hemispherical to convex or expanded, umbilicate or at least depressed at the centre, whitish, beige or sometimes light brown, dry, radially fibrillose, striate near the margin, hygrophanous. Lamellae (L 4-8, l 1-(3)), sinuate to subdecurrent, grey or beige when young, becoming beigepink, gill edge concolorous. Stipe 10-20 x 1-1.5 mm, cylindrical or attenuated downwards, concolorous with pileus, with white weft at the base, dry, fibrillose, hollow, often cespitose. Context whitish. Odor and taste strongly farinaceous or rancid.
Spores 10-12.5 x 8-10 µm, subglobose with 5-6 blunt angles, prominent apiculus. Basidia 45-80 x 12 µm, 4-spored (35-50 x 10-11 µm in 2-spored basidia). Cheilo- and pleurocystidia none. Caulocystidia 30-50 x 4-7 µm, fusoid-subcapitate, hyaline. Cuticle a cutis of cylindrical hyphae (5-16 µm diam.), terminal cells sometimes fusoid with rounded neck, membrane thin-walled and not gelatinized, encrusted by brown pigment. Clamp connections present.

On soil among mosses and litter in and along the margin of forests (Nothofagus spp., Leptospermum spp., Podocarpus ferrugineus, Weinmannia racemosa). New Zealand

Pileo 5-12 mm lato, ex hemisphaerico umbilicato, centro concavo, albidulo vel brunneolo, sicco, vix striato, hygrophano, glabro. Lamellis sinuato-decurrentibus, griseo-argillaceis demum roseis, acie concolori instructis. 8tipite 10-20 x 1-1.5 mm, cylindrico vel basim versus attenuato, pileo concolori, fibrilloso, sicco frequenter connato. Odore saporeque farinaceo. Sporis 10-12.5 x 8-10 µm, subgloboso-angulatis. Basidiis 4-sporigeris, frequ. 2-sporigeris. Cheilo- et pleurocystidiis nullis. Caulocystidiis inconspicuis, sed praesentibus. Epicute ex hyphis cylindraceis cutem formantibus, pigmento brunneolo incrustatis, fibuligeris. Ad terram inter muscos in silvis. Novazelandia.

E. rancidulum shows some affinities with E. floridanum (Murrill) Hesler and E. subplanum (peck) Hesler. The carpophores of the New Zealand species, however,are in general smaller and the spores also differ considerably in shape from those of the two North American species.

Holotypus (PDD 27017): 'Denton River, Te Anau Downs, N.Z.; leg. Horak, l.IV.1969'.